Black Mountain Pass

The A4069 crosses the Black Mountain at the western end of the Brecon Beacons, running about 20 miles from Llandovery through Llangadog to Brynamman. It climbs to 493 m over open moorland and is one of the most filmed roads in Britain, a regular backdrop for television road tests.

The drive

North to south is the better direction. After Llangadog the road climbs through trees, breaks out onto the open hill and runs through a series of well-sighted, cambered bends to the summit car park. The descent towards Brynamman includes the Tro Gwcw, or Cuckoo Turn, a tight downhill hairpin.

Link it with the A4067 past Cray reservoir and the mountain road from Trecastle to make a loop of an hour or so.

In your Porsche

A good road for any Porsche at legal speeds: well sighted, cambered and wide enough that a 911 is not a squeeze. The Tro Gwcw hairpin is a neat demonstration of rear-engine traction on the way out. The limit is now 40 mph over part of the mountain section, so go for the views and the rhythm.